34 00 050 Bleeding Brake System With DSC

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2008 BMW 750i, 2008 BMW 750Li, 2007 BMW 750i, 2007 BMW 750Li, and 2006 BMW 750i. However, it is still accessible from the selected car via links, so may be relevant.

Necessary preliminary tasks:

Read and comply with General Information See 34 00 ... GENERAL INFORMATION
Remove air duct from microfilter on left See 64 31 031 REMOVING AND INSTALLING/REPLACING LEFT OR RIGHT MICROFILTER AIR DUCT (AUTOMATIC A/C HIGH)

Observe safety when raising the vehicle.

Observe filling and bleeding instructions when replacing or repairing:

Brake master cylinder
Hydraulic unit
Components and connecting lines which are fitted between these assemblies.
Precharging pump

After work has been carried out on the precharging pump, only the front-axle brake circuit has to be bled. Before flushing the brake system, activate the precharging pump once with the Diagnosis and Information System (DIS) (bleeder unit connected with max. 2 bar filling pressure).

Connect BMW Diagnosis and Information System (DIS).
Call up service function for bleeding DSC hydraulics.
Connect bleeder unit to expansion tank and switch on.

NOTE:

Check relevant Operating Instructions for each device.

Charging pressure should not exceed 2 bar.

Fig 1: Connecting Bleeder Unit To Expansion Tank

Courtesy of BMW OF NORTH AMERICA, INC.

Flushing brake system completely

Connect bleeder hose with collecting tray to bleeder valve on rear right brake caliper.

Open bleeder valve and purge until clear, bubble-free brake fluid emerges.

Close bleed valve.

Follow same procedure on rear left, front right and front left wheel brake.

Fig 2: Connecting Bleeder Hose With Collecting Tray To Bleeder Valve On Rear Right Brake Caliper

Courtesy of BMW OF NORTH AMERICA, INC.

Bleeding rear-axle brake circuit

Connect bleeder hose with collecting tray to bleeder valve on rear right brake caliper.

Close bleeder valve.

Run through bleeding routine with BMW Diagnosis and Information System (DIS) with bleeder valve open.

After routine has finished, press brake pedal 5 times down to floor; clear bubble-free brake fluid must flow out.

Close bleed valve.

Repeat procedure at rear left.

Fig 3: Connecting Bleeder Hose With Collecting Tray To Bleeder Valve On Rear Right Brake Caliper

Courtesy of BMW OF NORTH AMERICA, INC.

Bleeding front-axle brake circuit

Connect bleeder hose with collecting tray to bleeder valve on front right brake caliper.

Close bleeder valve.

Run through bleeding routine with BMW Diagnosis and Information System (DIS) with bleeder valve open.

After routine has finished, press brake pedal 5 times down to floor; clear bubble-free brake fluid must flow out.

Close bleed valve.

Repeat procedure at front left.

Fig 4: Bleeding Front-Axle Brake Circuit

Courtesy of BMW OF NORTH AMERICA, INC.

Switch off brake fluid changer and remove from expansion tank.

Check brake fluid level.

Close expansion tank.

NOTE: Take care of rubber gasket (1) in lid.

Fig 5: Identifying Rubber Seal In Sealing Cap

Courtesy of BMW OF NORTH AMERICA, INC.